Users are no longer required to use the -clean/-force argument to force a complete uninstall of Flash Player when using the stand-alone uninstaller.

With the release of Flash Player 10.1 (Argo), the command-line arguments have changed significantly. If you use Windows Vista and have an earlier player, update it. Note: When testing for Windows Vista, the earliest player that is supported is 9.0.28.0. If the installation fails, follow the instructions in Install an earlier version of Flash Player | Internet Explorer | Windows. For example, if you installed Flash Player 9.0.47.0, and attempted to install version 9.0.45.0, the installation failed. If you previously installed a later version of Flash Player for Internet Explorer, you can be prevented from installing an earlier version. Installing prior versions of Flash Player can fail. If you want to switch from a later to an earlier version of Flash Player, Adobe recommends that you completely remove one version before you install another. (This uninstaller is available in Uninstall Flash Player | Windows.) This unistaller is a general-purpose uninstaller that you can use to remove any version of Flash Player.

The general uninstaller (uninstall_flash_player.exe) is designed to work with the new version-checking logic, and you can use it to remove Flash Player from the system. Select the appropriate Flash Player version.

Adobe flash player 10.1 release date